1. Field of the Invention
The invention relates to a motor structure.
2. Description of the Related Art
As shown in FIG. 1 and FIG. 2, a conventional motor structure includes a stator assembly and a rotor assembly. The stator assembly includes a stator core 1 and a winding. The stator core 1 includes a yoke 10 and a plurality of teeth 11 protruding inwards from the yoke 10. Two adjacent teeth 11 form a wire embedding slot 12. The winding is placed inside the wire embedding slot 12 and winds around the teeth 11. The rotor assembly includes a rotor core 2 and a permanent magnet 3. The rotor core 2 includes an annular ring 21 having a central axial pore 20 and a plurality of magnetic induction blocks 22 protruding outwards from outside of the annular ring 21. Two adjacent magnetic induction blocks 22 form a radial recess 23, and the permanent magnet 3 is mounted inside the recess 23. As shown in FIG. 1, outer contours of both the magnetic induction blocks 22 and the teeth 11 are formed by an arc-shaped line. As shown in FIG. 2, outer contour of the magnetic induction blocks 22 is formed by an arc-shaped line while that of the teeth 11 is formed by a straight line. Such structure has the disadvantages of higher stator's cogging torque, larger magnetic leakage between the stator and rotor teeth, and distorted top waveform of counter-electromotive force, thereby affecting the motor's service performance.